Hello guys i am in the prosses of building my 3rd layout i have a question for you guys be for i continue building. i plan on useing homasote for my base. the benchwork is open grid 2 feet wide. my frist layout i just used a plywood top my 2nd i used plywood and 2" foam bored i have never used homasote. so here go’s the question have any of you guys just layed down the homasote with out a plywood base is it stable enough or will it get saggy where theres no suport between cross spines ? the layout is in a spare room in my house no basement so it will be heated and cooled as you would your home
My experience is that Homasote is NOT stiff enough on its own to be self-supporting, epecially with support at 2ft intervals. It is perhaps stiff enough for supposts spaced at 12", but I wouldn’t want to go more than that. This assumes the Homasote is laid horizontally as a 1/2" thick sheet.
Home Depot has some 3.5" wide Homasote strips to use as concrete forms and spacers. I would buy a strip or two, and experiment with it to prove to yourself what the spacing can be. If you do the math, even a 0.05" (1/20") sag between supports spaced at 2ft means a 0.4% grade, and free-rolling cars will start rolling by gravity.
Homasote has also been used as a group of 1.5" strips glued together and mounted vertically. This is a very strong and capable construction method, capable of supports more than 2 ft apart. Expansion and contraction of Homasote with temperature/humidity is on a par with plywood, so no real issues there.
just my experiences
Fred W
Homasote by itself is definitely NOT strong enough to support your railroad. It is essentially recycled newsprint with some sort of binder formed into sheets under pressure. It is great stuff but needs support underneath. If your joists are 24" apart, I recommend 3/4 " plywood to avoid sagging. Or very good (ie cabinet grade) 1/2" plywood.
thanks guys for ter quick answers my suports are 14" apart. i have some scrap piceses i will just set it up on the top and put some weight on it and see what happens…i am a seasonal employee so i am on unempolyment right now so money is tight i wanted to use what have but i also want to do it right so time for an experment
Never take shortcuts with the most important part of your Layout -
A good support for your trackwork!
A plywood or OSB base of 1/2" or thicker base is a minimum to support the homasote!
Also your support joists should be spaced no more then 16" apart
Anything wider and the Plywood or OSB will beging to sag - unless it is 3/4" or more!
Humidity works wonders on a wood product layout base!
Then Glue and Screw the Homasote to the base material
You will have a layout base that will last a lifetime!
BOB H - Clarion, PA
My current layout and final is 121/2x40x121/2, 1/2 inch, exterior ply one side smooth with 1/2 Homosote on top, 1x3 open grid framing has been standing 25yrs in my attic, but the attic is finished and temp. controlled, absolutely never had any problem’s with it and I live in the four season’s Mid-West. I also use the ‘‘Old Fashion style Aluminum screen on the open grid areas’’.
Take Care!
Frank
If you run Bowser steam 3/4" plywood can sag.
I have 8 4x8 sheets of homasote used in my yard and I have support every 12 inches with no sagging, a friend went 16 on center and had a lot of sagging between the supports so I would not go more than 12" on centers.Jim.
You may not see how the material will perform in the long term with an experiment like that. Homasote is rarely suitable for use without a solid support beneath it. If money is tight, talk to some local building contractors about saving scraps of plywood or OSB for use under the Homasote. Eventually unsupported Homasote is likely to deform and ruin whatever you build on top of it.
Back when a lot of people were saying sure, no problem, you cna use Homasote by itself, I built a small (2x4 I think it was) N scale layout on a piece of Homasote. It mostly sat on a tabletop, but eventually I had extra grades - the center sagged so going from one nef towards the center it was downhill and then going from the center to the edge was back uphill again. It took months if not longer for the sag to develop - everything was perfectly fine at first. And there was no heavy scenery, it was all flatlands with a few plastic structures and ground foam, no plastic hills or anything.
It was from that experience that I don;t understand how people say Homasote holds spike for handlaying track - the track (sectional and flex) and cork roadbad on that layout were fasted with track nails - I was able to pull all of it up by hand, very easily, to reuse it all on the next layout I built, which went back to a more traditional plywood surface. Even when I was laying the track, the cork offered much more resistence than the Homasote, i was able to press the nails in in many cases, no hammering - which can be a plus, an off center hit with the hammer can skew the track and cause kinks. It’s certainly very easy to press nails and spikes into Homasote, but I think any ‘holding power’ you get is from the wood ties.
–Randy
I must disagree, Randy. I have Homabed on 1/2" Homasote (also Homasote without Homabed) and spike (not nail) all my Walthers/Shinohara Code 83 track and turnouts. The spikes hold just fine. Just because you can pull them (with a tool) doesn’t mean they don’t hold adequately.
Regarding the support of the Homasote, I agree with those who recommend plywood under the Homasote. I have op
[quote user=“dante”]
rrinker
Back when a lot of people were saying sure, no problem, you cna use Homasote by itself, I built a small (2x4 I think it was) N scale layout on a piece of Homasote. It mostly sat on a tabletop, but eventually I had extra grades - the center sagged so going from one nef towards the center it was downhill and then going from the center to the edge was back uphill again. It took months if not longer for the sag to develop - everything was perfectly fine at first. And there was no heavy scenery, it was all flatlands with a few plastic structures and ground foam, no plastic hills or anything.
It was from that experience that I don;t understand how people say Homasote holds spike for handlaying track - the track (sectional and flex) and cork roadbad on that layout were fasted with track nails - I was able to pull all of it up by hand, very easily, to reuse it all on the next layout I built, which went back to a more traditional plywood surface. Even when I was laying the track, the cork offered much more resistence than the Homasote, i was able to press the nails in in many cases, no hammering - which can be a plus, an off center hit with the hammer can skew the track and cause kinks. It’s certainly very easy to press nails and spikes into Homasote, but I think any ‘holding power’ you get is from the wood ties.
–Randy
I must disagree, Randy. I have Homabed on 1/2" Homasote (also Homasote without Homabed) and spike (not nail) all my Walthers/Shinohara Code 83 track and turnouts. The spikes ho
Yeah, I’ll have to agree about the Homosote holding better than cork, one reason being it is more denser than cork. I have at least 15 Caboose Ind. ground throws that are held in with, ‘‘perfect’’ brand 0 x 3/8’’ round head black wood screws and if I need to replace one, I just unscrew two screws and put the new one into the same holes and it works everytime. Track is held down with ME round head track spikes, every 4 inches in the center holes of the ties, once ballasted you don’t see the spike heads and the track is not going anywhere, all c83 Atlas flex. I was going to use cork roadbed, but being fortunate to have a table saw, I made my own with Homosote. Still have a case of cork roadbed under the layout.
Frank
I’ll chime in here too on Homasote and Homabed. It works fine for holding spikes and track nails on two layouts I’ve built.
thanks everybody for the coments i am going to put plywood down just to be safe…dont fix it if its not broke right
My high school HO layout (apx. 4’x6’ with later 2’x6’ addition) had 1/2" homasote on box-grid benchwork using 1"x4" support underneath in 2’x3’ and 2’x4’ box-grid sections = No homasote sagging.
A later 4’x4’ N Scale Christmas Tree layout lasted 30+ years with 2’x4’ underlying box-grid support = No Homasote sagging. Note: Western PA does have variable humidity, and had no noticable effect on either layout.
Due to traction pole support needs, CR&T is looking at a plywood base, not homasote this time around.
The primary benchwork strategy, also mentiond previously, needs to be a “take no prisoners” attutude for durable layout benchwork strength, specific for your circumstances. Thus: 1/2" homasote on top of 1/2" plywood is certainly a “take no prisoners” approach – Plywood is also more effective for mounting wiring, and switch machines, underneath the layout – Whereas, homasote is second to none for track spiking.
Pull cork up and the nails rip through it but stay in the homasote? I’d LOVE to see that demonstrated. Pulling on the cork would just pull the nails right out of the homasote. Plywood instead of homasote, or nails long enough to reach through the homasote into the plywood - yes, then unless the nail has a large flat head, it will simply pull through the cork leaving a nail sticking up.
I’m sure it’s ‘adequate’, especially after you add ballast. And my track didn’t shift around, it did stay in place. So sure, it’s ‘adequate’. I no longer bother with nails or spikes, it’s all held in place with latex caulk.
–Randy
Homosote needs plywood under it. I used Homosote over open grid, and even with cross grids at 12 inches, the homosote eventually sags. It does hold track nails. But it sags just from it’s own weight, over time. I am constantly adding cross braces and shoreing up sagging track. A full 4 by 8 sheet might be OK, but if you cut strips 4 or 5 inches wide for track, it surely will sag. My layout is too far along to start over, so I continue to add supports, sometimes only 4 to 6 inches apart. I would never again use homosote alone, without plywood under it.
Yeah. That’s how I took apart my last three layouts that never made it to the scenery stage. Pulled the track up, then just ripped the cork off instead of trying to find all those tiny nail heads. Easier to find them when they’re sticking up out of the contrasting gray Homasote.
My spikes are only in the Homasote, not through it into the plywood. And no ballast or shifting track yet, either.
Dante